1. Field
Embodiments of the present disclosure relate to a magnetic regenerator unit using a magnetocaloric effect of magnetocaloric materials and a magnetic cooling system having the same.
2. Description of the Related Art
A magnetic cooling system is configured to use a feature of magnetocaloric materials, which generates heat when magnetized by a magnetic field, and absorbs heat when demagnetized by an outer magnetic field. In addition, the magnetic cooling system may replace conventional cooling apparatuses, which use an air compression cycle.
Generally, a magnetic cooling system includes a magnetic regenerator formed of magnetocaloric materials, a flux generator for obtaining a magnetocaloric effect from the magnetocaloric materials, a fluid supply device for forming a thermal gradient from the magnetocaloric effect, a heat exchanger for absorbing heat from the outside or for emitting heat to the outside by using the thermal gradient, and the like.
In the magnetic cooling system, the flux generator including an external stator and an internal rotator is provided with magnetocaloric materials evenly arranged on an inner surface of the stator to reduce torque of the rotator so as to obtain high efficiency. When the magnetocaloric material is evenly arranged on the inner surface of the stator, the flux generator, which is formed in a shape of an oval, is divided into a magnetization area into a demagnetization area.
In the oval-shaped flux generator, an area where the change of the magnetic field is increased, and an area where the change of the magnetic field is decreased appear by rotation of permanent magnets so the flow of heat transfer fluid may not correspond to the change of the magnetic field. When the change of the magnetic field and the flow of the heat transfer fluid are proportionally changed, the flux generator may obtain a maximum cooling capacity. However, in the oval shaped flux generator, the heat transfer fluid may not be proportionally changed and may not evenly flow so that the maximum cooling capacity may not be obtained when considering the amount of material.